Aspects relate to airplanes having a blended wing body. A blended wing body may include a fuselage and a port wing and a starboard wing continuously coupled to the fuselage and a nose section. A midship control surface may be disposed on a trailing edge of the blended wing body and centered between the port wing and the starboard wing.

A main rotor trim tab retention system includes, a blade housing having flanges separated by a cavity defined between the flanges, and a trim tab assembly. The trim tab assembly includes, a trim tab having an aerodynamic surface, at least one arm extending from the trim tab positionable within the cavity while the trim tab extends outward from the cavity, and a spherical bearing connecting the trim tab and the at least one arm, the spherical bearing having a first axis which is substantially perpendicular to the aerodynamic surface of the trim tab. The at least one arm is pivotable about the spherical bearing about a second axis substantially perpendicular to the first axis to rotate the trim tab relative to the blade housing.

A low stall or minimum control speed aircraft comprising a fuselage that has vertically flat sides; wings with high a lift airfoil profile of constant chord section set at zero degree planform sweep, twin booms having inner vertically flat surfaces, twin vertical stabilizers, a flying horizontal stabilizer; preferably twin engines having propellers and wherein each engine preferably has a thrust-line that is inclined nose-up to a maximum of +8 degrees, and is parallel to the wing chord underneath wing mounts and landing gear doors that provide surfaces for channeling propeller wash in a rearward direction; all working in concert so that the airplane has an extremely low stall speed and minimum control speed. The engines may be diesel, hydrogen fuel cell, electric fuel cell, diesel-electric, gas turbine or combinations thereof. The propellers may be counter-rotating.

While an aircraft is mid-flight, a braking start point associated with a stoppable rotor is calculated where the stoppable rotor includes a first and second blade and the stoppable rotor is configured to rotate about a substantially vertical axis. A process to stop the stoppable rotor is started, while the aircraft is mid-flight, when the stoppable rotor reaches the braking start point, where the stoppable rotor is stopped with the first blade pointing forward and the second blade pointing backward.

In one embodiment, an apparatus includes a first deflector configured to couple to a shaft of an aircraft. The first deflector may form part of a top surface of the aircraft when in a first closed position. The apparatus may further include a second deflector configured to couple to the shaft and form part of a bottom surface of the aircraft when in a second closed position. The first deflector and the second deflector may be configured to be positioned at a junction of a body of the aircraft and a wing of the aircraft. The first deflector and the second deflector may be configured to simultaneously pivot from the closed positions to respective first and second open positions upon actuation of the shaft.

Provided are a flap drive device and a rotorcraft blade, and more particularly, a flap drive device using a two-section link mechanism, which may be applied to a rotorcraft blade, and a rotorcraft blade including the same.

Apparatus for improving flow characteristics around aircraft wings by obstructing air flow through an aperture formed in a wing skin for a movable duct or track are disclosed. In one embodiment, the apparatus comprises a substantially rigid panel movable at least partially across the aperture for at least partially occluding the aperture and for accommodating movement of a slat track extending through the aperture. In another embodiment, the apparatus comprises a hinged panel configured to swing outwardly from an outer side of the wing skin toward an open position to accommodate movement of an anti-icing duct extending through the aperture and to swing toward a closed position at least partially occluding the aperture.

A blade (1) having an outer covering (2) defining a cavity (8). A carriage (20) is arranged in said cavity (8), the carriage (20) being provided with a torsion bar (21) and at least two arms (22) secured to the torsion bar (21). The blade has one connection per arm provided both with an upstream guide gallery and with a downstream guide gallery, each arm extending transversely from an upstream end that slides in an upstream guide gallery to a downstream end that slides in a downstream guide gallery. At least one connection is a helical connection (40) obtained with the help of an upstream guide gallery (33) and the downstream guide gallery (34) of the segment (101) presenting distinct orientations, giving rise to movement in rotation (ROT1) of the segment (101) under the effect of the carriage (20) moving in translation.

A system and method for estimating rotor mixing commands for an aircraft includes receiving signals indicative of reference commands from one or more controllers; receiving signals indicative of airspeed and sideslip angle for the aircraft, the sideslip angle being indicative of a direction of flight for the aircraft; calculating a sine and cosine of the sideslip angle; determining gains for roll and pitch as a function of the airspeed, the determining including referencing a look-up table that indexes the gain constants with the airspeed; and determining the one or more rotor mixing commands from the determined gains, the one or more rotor mixing commands being applied synchronously to the rotors in the aircraft.

An aerial vehicle including a frame, a housing at least partially enclosing the frame, and a flap assembly mounted to at least one of the frame and the housing. The flap assembly can include a flap and an actuator. The aerial vehicle further can include a communication device coupled to the flap. The actuator can be operable to move the flap relative to the housing to at least partially maintain an orientation of the communication device relative to a remote system.